Renewable sources of energy such as wind and solar power are intermittent. The wind doesn’t always blow; the sun doesn’t always shine. But power grids need uninterrupted, reliable flows of energy in order to guarantee electricity to masses. If renewable energy is to come online with coal and natural gas, it can’t be sporadic. That means it needs to be efficiently stored so it can be utilized on cloudy, windless days and at night.

Britain’s Highview Power Storage has developed an unusual way to store energy generated by wind and sunlight: liquid air. Sound cool? It is, quite literally.

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